The present invention relates to an apparatus for drying granular material which includes an improved heat exchange assembly that efficiently utilizes the heat generated by combustion within a burner without the danger of having flames or sparks directly impinge upon the granular material being dried.
In conventional grain dryers, the combustion gas output of a burner unit, typically a propane gas burner with a high power output blower, is introduced into the dryer so as to directly impinge upon wet granular material being conducted through a drying column. The flow of hot combustion gas through the granular material in the drying column dries the granular material by causing unwanted moisture to be evaporated therefrom. Although this type of dryer is generally effective for drying certain types of grain, such as corn, when this type of dryer is employed to dry other granular products, such as sunflower seeds, safflower seeds, soybeans, or other types of oil-based seeds, sparks or flames within the flow of combustion gas from the burner may directly impinge on the granular material and result in the possibility of fires caused by the ignition of granular material within the drying column.